Skip to main content

Successful dilation and evacuation for second trimester conjoined twin: a case report and review of the literature



Conjoined twins are a rare clinical event occurring in about 1 per 250,000 live births. Though the prognosis of conjoined twins is generally low, there is limited evidence as to the optimal method of pregnancy termination, particularly in cases of advanced gestational age. We report a successful dilation and evacuation (D&E) done for conjoined twins at 22 weeks of gestation.

Case presentation

A 20-year-old primigravid woman was diagnosed with a conjoined, thoraco-omphalopagus twin pregnancy after undergoing a detailed two-dimensional (2D) fetal ultrasound anatomic scanning. Assessment and counseling were done by a multidisciplinary team. The team discussed the prognosis and options of management with the patient. The patient opted for termination of pregnancy. Different options of termination were discussed and the patient consented for D&E, with the possibility of reverting to hysterotomy in case intraoperative difficulty was encountered. A 2-day cervical preparation followed by D&E was done under spinal anesthesia and ultrasound guidance.


In this patient, D&E was done successfully without complications. Adequate cervical preparation, pain control, and ultrasound guidance during the procedure are critical for optimal outcomes. A literature review of methods of pregnancy termination for conjoined twins in the second trimester revealed 75% delivered vaginally through medical induction while 18% underwent cesarean section. Only one other report described successful D&E for conjoined twins after 20 weeks. D&E can be safely performed for carefully selected cases of conjoined twins beyond 20 weeks’ gestations avoiding the need for induction or hysterotomy.

Peer Review reports


Conjoined twins are extremely rare, occurring in about 1 per 50,000 pregnancies and 1 per 250,000 live births. Though the prognosis of conjoined twins depends on the degree and location of union, it is generally associated with high perinatal mortality and patients may request termination of pregnancy [1, 2]. However, there is limited evidence as to the optimal method of pregnancy termination particularly in cases of advanced gestational age. Though medical terminations of conjoined twin pregnancies have been documented up to late second trimester, the use of surgical methods is not widely reported [3, 4]. Here we report a case of conjoined twins successfully managed with dilation and evacuation (D&E) and systematically review previously reported cases to analyze methods of pregnancy termination for conjoined twins in the second trimester.

Case presentation

A 20-year-old primigravid woman was referred to our hospital at 22 weeks of gestation with a diagnosis of large fetal intra-abdominal cysts identified during a routine ultrasound examination. In our center, detailed fetal two-dimensional (2D) ultrasound anatomic scanning was done, revealing two fetal heads at a fixed position, facing each other (Fig. 1). There was a fused chest and abdomen with a single shared distorted heart and one aorta. A single umbilical cord was noted. There was a single shared liver. The kidneys appeared enlarged with multiple non-communicating cysts and thinned-out cortical tissue. Two separate spines were visualized on either side of the uterine cavity (Fig. 2). Conjoined, thoraco-omphalopagus twin pregnancy was diagnosed. Fetal karyotyping was offered but declined by the family.

Fig. 1
figure 1

Axial ultrasound image showing two normally shaped fetal heads facing each other

Fig. 2
figure 2

Sagittal section of the fetal chest and abdomen showing two fetal spines, a single distorted heart, and multicystic kidneys

Assessment and counseling were done by a multidisciplinary team composed of obstetricians, fetal medicine specialists, family planning specialists, and anesthetists. After discussion on prognosis and options of management, the patient opted for termination of pregnancy. Different options of termination were discussed and the patient consented for D&E, with the possibility of reverting to hysterotomy in case intraoperative difficulty was encountered.

We performed a 2-day cervical preparation. On day 1, 200 mg mifepristone was administered orally and five laminaria were inserted. On day 2, the patient was admitted and a new set of 10 laminaria were inserted. On the morning of the procedure, she was provided with 400 µg misoprostol sublingually and 200 mg doxycycline orally. After 2 hours she was transferred to the operating room and spinal anesthesia was given. D&E was done under ultrasound guidance. We started the procedure by rupturing the membranes to bring down fetal parts to the lower uterine segment. Initial extraction of fetal parts was done by disarticulating and removing the extremities. Decompression of the thoracic and abdominal cavity allowed further descent and separation of the thoracopagus. The presenting calvarium was decompressed with suction and delivered. Finally, the second twin and placenta were delivered intact. The procedure was completed without complications. Post-procedure tissue count showed two calvaria and spines, four well-formed upper limbs, single thorax and abdomen, and two well-formed and two fused primitive lower limbs. The patient recovered well and was discharged after 24 hours. A follow-up phone call after 2 weeks revealed an uneventful course.


Conjoined twins are rare. The available management options are usually complex and ample experience with case management is limited to few centers worldwide [1]. Recent advances in antenatal imaging techniques, such as three-dimensional (3D) ultrasonography, Doppler studies, and magnetic resonance imaging (MRI), enable diagnosis as early as 12 weeks’ gestation. In addition, detailed prenatal anatomic scanning will define the extent of organ sharing and inform prognosis [2, 5]. Early diagnosis followed by thorough counseling on the likely prognosis is crucial for optimal management [3, 6]. However, as in our case, early diagnosis can be missed and the pregnancy may advance into the second trimester. Other reports from developing countries also show the diagnosis of conjoined twins may be delayed until the third trimester or even up to the time of labor and delivery [7, 8].

Conjoined twins with a shared heart are associated with extremely poor prognosis, and separation and survival of both twins (or even one) is unlikely [2, 9]. Given this, our patient decided to terminate her pregnancy.

Pregnancy termination for conjoined twins in later gestation is often accomplished through hysterotomy because of perceived difficulty in vaginal delivery [10]. Though details of the methods employed were not described, Brizot et al. reported 12 vaginal terminations for second trimester conjoined twins [9]. Similarly, Mitchell et al. reported two successful inductions of late second trimester conjoined twins. However, both patients underwent two sessions of laminaria placement prior to administration of uterotonics [4].

We conducted a systematic search of the electronic databases of MEDLINE, EMBASE, and Google Scholar using MeSH and keywords from the inception of the databases until November 30, 2020 (see Additional file 1). Bibliographies of the relevant articles were reviewed and then cross-searched to identify further relevant studies. We included all publications in English that specify the method of pregnancy termination for conjoined twins in the second trimester (14–28 weeks).

Two authors (FAA and THT) independently performed study screening and data extraction. Titles and abstracts were screened to identify eligible articles, and full text was obtained if both reviewers judged a citation to be potentially eligible. Standardized screening and data extraction forms were created prior to data collection. Extracted data include author, year of publication, the specific type of conjoined twin, gestational age at termination of pregnancy, method of pregnancy termination, and adverse maternal outcome or procedure-related complications (hemorrhage, blood transfusion, uterine rupture, sepsis, or death). Any discrepancies were resolved through discussion with a third reviewer (MDF).

Our initial search identified 512 publications. There were 392 articles after duplicates were removed. Examination of title and abstract led to the exclusion of 264 articles. The remaining 128 articles were assessed for eligibility by examining the full text. Of these, 95 were excluded as they did not meet the review inclusion criteria. Thus, our search identified 33 relevant publications with 47 previously reported cases to be eligible. With the addition of the present case, we therefore included a total of 48 cases from 34 publications for this review. Figure 3 presents the PRISMA flow diagram illustrating the systematic selection process.

Fig. 3
figure 3

PRISMA flow diagram study screening and selection

Most authors resort to medical induction of labor resulting in vaginal delivery; 75% of reviewed cases delivered vaginally through medical induction while 18% underwent cesarean section (Table 1).

Table 1 Methods of pregnancy termination for second trimester conjoined twins

Successful induction of labor has been reported for thoracopagus conjoined twins at 27 weeks of gestation [10, 11]. Nevertheless, we identified a few cases of cesarean section performed as early as 20 weeks [12,13,14].

None of the papers reviewed report adverse maternal outcomes. However, Mitchell et al. reported a case complicated by chorioamnionitis. The patient underwent two sessions of laminaria insertion 24 hours apart and was provided with prophylactic antibiotics. Chorioamnionitis was diagnosed on the basis of high-grade fever and tachycardia. She was treated with intravenous antibiotics and was discharged 2 days after successful induction labor [4].

There are limited data on utilization of surgical abortion for conjoined twins. To our knowledge, there is only one report describing successful D&E for conjoined twins after 20 weeks [15]. Although D&E offers a shorter procedure time and avoids the need for induction or hysterotomy, it is not of course without complications, particularly at later gestations. Thus, it should be reserved for specialized centers with experienced providers [3].

When performing D&E, adequate cervical preparation is an important intervention to reduce the risk of procedure-related complications including uterine trauma and cervical laceration. This is especially true in advanced gestational age or, as in our case, when difficulty is anticipated [16, 17]. We achieved adequate cervical preparation with 2 days’ preparation, using a combination of medical and mechanical methods.

The routine use of ultrasound during surgical abortion is controversial. However, ultrasound guidance has been shown to increase safety and facilitate completion of the procedure in difficult cases [18]. We utilized ultrasound throughout the procedure to localize fetal parts and guide our instruments in the uterus.


Even though this is experience from a single case, D&E can be safely performed for carefully selected cases of conjoined twins beyond 20 weeks’ gestations. Adequate cervical preparation, pain control, and ultrasound guidance during the procedure are critical for optimal outcomes.

Availability of data and materials

All data generated or analyzed during this study are included in this published article and its supplementary information files.


  1. Spitz L, Kiely E. Experience in the management of conjoined twins. Br J Surg. 2002;89:1188–92.

    Article  CAS  PubMed  Google Scholar 

  2. Spitz L. Conjoined twins. Prenat Diagn. 2005;25:814–9.

    Article  PubMed  Google Scholar 

  3. O’Brien P, Nugent M, Khalil A. Prenatal diagnosis and obstetric management. Semin Pediatr Surg. 2015;24(5):203–6.

  4. Mitchell T, Cheng E, Jolley J, Delaney S. Successful induction of labor of late-second-trimester conjoined twins: an alternative to hysterotomy. Obstet Gynecol. 2014;123:469–72.

    Article  PubMed  Google Scholar 

  5. Osmanağaoğlu MA, Aran T, Güven S, Kart C, Özdemir Ö, Bozkaya H. Thoracopagus conjoined twins: a case report. ISRN Obstet Gynecol. 2011;2011:89.

    Article  Google Scholar 

  6. Sen C, Çelik E, Vural A, Kepkep K. Antenatal diagnosis and prognosis of conjoined twins–a case report. J Perinat Med. 2003;31:427–30.

    PubMed  Google Scholar 

  7. Gaym A, Berhan Y, Abadi GS, Wubishet T. Thoracopagus conjoint twins presenting as shoulder dystocia: a case report. Ethiop Med J. 2004;42:303.

    PubMed  Google Scholar 

  8. Mohammad MA, Anyanwu LJC, Abdullahi LB, et al. Management of conjoined twins in Kano, Nigeria: our experience and challenges in a low-resource setting. Nigerian J Basic Clin Sci. 2018;15:92.

    Article  Google Scholar 

  9. Brizot M, Liao A, Lopes L, et al. Conjoined twins pregnancies: experience with 36 cases from a single center. Prenat Diagn. 2011;31:1120–5.

    CAS  PubMed  Google Scholar 

  10. Sakala EP. Obstetric management of conjoined twins. Obstet Gynecol. 1986;67:21S-25S.

    Article  CAS  PubMed  Google Scholar 

  11. Singla V, Singh P, Gupta P, Gainder S, Garg M, Khandelwal N. Prenatal diagnosis of thoracopagus fetus: a case report with brief review of literature. Arch Gynecol Obstet. 2009;280:1025.

    Article  PubMed  Google Scholar 

  12. Balakumar K. Conjointed twins with jugular lymphatic obstruction sequence. Indian Pediatr. 1995;32:365–8.

    CAS  PubMed  Google Scholar 

  13. Camuzcuoglu H, Toy H, Vural M, Cece H, Aydin H. Prenatal diagnosis of dicephalic parapagus conjoined twins. Arch Gynecol Obstet. 2010;281:565–7.

    Article  PubMed  Google Scholar 

  14. Ozcan HC, Ugur MG, Mustafa A, Kutlar I. Conjoined twins in a triplet pregnancy: a rare obstetrical dilemma. Saudi Med J. 2017;38:307.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Hern WM, Landgren B. Dilation and evacuation of thoracopagus conjoined twins per vagina at 26 weeks [20I]. Obstet Gynecol. 2019;133:100S.

    Article  Google Scholar 

  16. Hayes JL, Fox MC. Cervical dilation in second-trimester abortion. Clin Obstet Gynecol. 2009;52:171–8.

    Article  PubMed  Google Scholar 

  17. Fox MC, Krajewski CM. Cervical preparation for second-trimester surgical abortion prior to 20 weeks’ gestation. Contraception. 2014;89:75–84.

    Article  PubMed  Google Scholar 

  18. Darney PD, Sweet RL. Routine intraoperative ultrasonography for second trimester abortion reduces incidence of uterine perforation. J Ultrasound Med. 1989;8:71–5.

    Article  CAS  PubMed  Google Scholar 

  19. Kattel P. Conjoined twins. J Nepal Med Assoc. 2018;56:88.

    Google Scholar 

  20. Chatkupt S, Chatkupt S, Kohut G, Chervenak FA. Antepartum diagnosis of discordant anencephaly in dicephalic conjoined twins. J Clin Ultrasound. 1993;21:138–42.

    Article  CAS  PubMed  Google Scholar 

  21. Zoppini C, Vanzulli A, Kustermann A, Rizzuti T, Selicorni A, Nicolini U. Prenatal diagnosis of anatomical connections in conjoined twins by use of contrast magnetic resonance imaging. Prenat Diagn. 1993;13:995–9.

    Article  CAS  PubMed  Google Scholar 

  22. Van den Brand S, Nijhuis J, Van Dongen P. Prenatal ultrasound diagnosis of conjoined twins. Obstet Gynecol Surv. 1994;49:656–62.

    PubMed  Google Scholar 

  23. Aquino DB, Timmons C, Burns D, Lowichik A. Craniopagus parasiticus: a case illustrating its relationship to craniopagus conjoined twinning. Pediatr Pathol Lab Med. 1997;17:939–44.

    Article  CAS  PubMed  Google Scholar 

  24. Esenkaya S, Gürbüz B, Yaltı S. Asymmetric parasitic dicephalus conjoined twins. J Clin Ultrasound. 2004;32:102–5.

    Article  PubMed  Google Scholar 

  25. Tansel T, Yazıcıoğlu F. Cardiac and other malformations in parapagus twins. Arch Gynecol Obstet. 2004;269:211–3.

    Article  PubMed  Google Scholar 

  26. Maymon R, Mendelovic S, Schachter M, Ron-El R, Weinraub Z, Herman A. Diagnosis of conjoined twins before 16 weeks’ gestation: the 4-year experience of one medical center. Prenatal Diagn. 2005;25:839–43.

    Article  Google Scholar 

  27. Hassani AA, Sandhu AK, Sundari MS. Dicephalus dibrachius with anencephaly. Saudi Med J. 2005;26:1634.

    PubMed  Google Scholar 

  28. Khanna PC, Pungavkar S, Patkar D. Ultrafast magnetic resonance imaging of cephalothoracopagus janiceps disymmetros. J Postgrad Med. 2005;51:228.

    CAS  PubMed  Google Scholar 

  29. Özkur A, Karaca M, Göçmen A, Bayram M, Sirikci A. Cephalopagus conjoined twins presented with encephalocele: diagnostic role of ultrafast MR imaging. Diagn Interv Radiol. 2006;12:90.

    PubMed  Google Scholar 

  30. Sabih D, Sabih Z, Worrall JA, Khan AN. Ultrasound diagnosis of dicephalic conjoined twins at 24 weeks of gestation. J Clin Ultrasound. 2010;38:328–31.

    PubMed  Google Scholar 

  31. Deveer R, Engin-Ustun Y, Kale I, Aktulay A, Danisman N, Mollamahmutoglu L. Anencephalic conjoined twins with mirror-image cleft lip and palate. Clin Exp Obstet Gynecol. 2010;37:231.

    CAS  PubMed  Google Scholar 

  32. Mete A, Cebesoy FB, Dıkensoy E, Kutlar İ. Dicephalic parapagus conjoined twins: a rare second trimester sonographic diagnosis. J Clin Ultrasound. 2010;38:89–90.

    Article  PubMed  Google Scholar 

  33. Pandey S, Mendiratta S, Pandey S, Sinha R, Pandey L. Conjoined twins with a single heart: a rare case report. Australas Med J. 2011;4:145.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Pătraşcu A, Stănescu M, Gheorman V, et al. Embryological, clinical and anatomopathological considerations on a very rare case of a bicephalous fetus (dicephalus dipus dibrachius). Roman J Morphol Embryol. 2013;54:427–31.

    Google Scholar 

  35. Wu Y, Lv Q, Xie MX, et al. Fetal echocardiographic characteristics of fused heart in thoracopagus conjoined twins. Echocardiography. 2014;31:E218–21.

    Article  PubMed  Google Scholar 

  36. Vaidya M, Ghike S, Jain S, Joshi S. Diprosopus: a rare conjoined twin. J South Asian Feder Obst Gynae. 2014;6:116–7.

    Article  Google Scholar 

  37. Krawczyk J, Borowski D, Węgrzyn P, Drews K. Siamese twins–prenatal diagnosis in the first trimester of pregnancy. Case study and review. Ginekol Pol. 2015;86:25.

    Article  Google Scholar 

  38. Lu Q, Xian C, He W, Li C, Li Y. Thoracopagus conjoined twins diagnosed by sonography. Int J Clin Exp Med. 2016;9:22679–82.

    Google Scholar 

  39. Biso M, Sala P, Vellone V, et al. Virtopsy in conjoined ischiopagus twins. Clin Exp Obstet Gynecol. 2017;44:288–91.

    CAS  PubMed  Google Scholar 

  40. Eris Yalcin S, Akkurt MO, Yavuz A, Yalcin Y, Sezik M. Prenatal sonographic diagnosis of cephalopagus conjoined twins at 14 weeks of pregnancy. J Clin Ultrasound. 2018;46:408–11.

    Article  PubMed  Google Scholar 

  41. Al Yaqoubi HN, Fatema N, Al Fahdi BS. A case of craniopagus parasiticus: an antenatal diagnosis by ultrasound screening at 16 weeks of gestation and a literature review of recently reported cases. Turk J Pediatr. 2019;61:941–5.

    Article  PubMed  Google Scholar 

  42. Vegar-Zubović S, Prevljak S, Behmen A, Bektešević H, Zubović D, Jusufbegović M. Conjoined twins–a case report of prenatal diagnosis of cephalothoracoomphalopagus. Radiography. 2020;26:e126–8.

    Article  PubMed  Google Scholar 

Download references


We wish to thank our patient for allowing us to share her unique case. We also wish to express our gratitude to all healthcare providers involved in her care.

The authors would like to acknowledge the Department of Obstetrics and Gynecology at Saint Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia.


This research did not receive any funding.

Author information

Authors and Affiliations



FAA, THT, MAS drafted the initial manuscript. FAA and THT did the literature search and analysis. MAS, MDF, and SP interpreted the data. WG, DB, and SP critically revised the manuscript for important intellectual content. All authors agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Ferid A. Abubeker.

Ethics declarations

Ethics approval and consent to participate

The study was approved by the institutional review board of Saint Paul’s Hospital Millennium Medical College.

Consent for publication

Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

Competing interests

The authors declare that they have no competing interests

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Additional file 1:

Search strategy.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit The Creative Commons Public Domain Dedication waiver ( applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Abubeker, F.A., Tufa, T.H., Shiferaw, M.A. et al. Successful dilation and evacuation for second trimester conjoined twin: a case report and review of the literature. J Med Case Reports 15, 298 (2021).

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: